Stabilization of airships



Sept. 15, 1931. w. v. N. POWELSON ET AL. 3,

STABILIZATION 0F AIR-SHIPS Original Filed Sept. 21, 1921 3 Sheets-Sheet 1 Sept. 15, 1931. w. VV-N. POWELSON ET AL 3,

STABILIZATION 0F AIRSHIPS Original Filed Sept. 21, 1921 3 Sheets-Sheet 5 Patented Sept. 15, 1931 PATENT OFFICE WILFRID V. N. POWELSON,

OF NEW YORK, :N. Y., AND WARREN TRAVELL, OF SAN BERNARDINO, CALIFORNIA STABILIZATION F AIRSHIPS Original application. filed September 21, 1921, Serial No. 502,127. Divided and this application filed November 25, 1930.

This invention pertains tofthe stabiliza-.

1o ground. This in the case of rigid airships is done by means mounted at the end of the ship, and in the case of nonrigid air- -ships is done by a yoke-like structure extending from the mooring device to loci near the. end of the ship. The axis of the ship assumes an angle determined by the relation of weights and buoyant forces on board, in-

- fluenced at times :by external forces, as winds. Such forces are constantly changing,

both in magnitude and in point of application, with consequent shifting of the ships position and departure from level keel, and constantrestoration byadjustments that are made on board. V Ships so moored have hitherto not been leveled, so far as weare aware, by means 7 functioning automatically in response to *movement ofthe free end of the airship, Malthough efforts have been made to hold the airship in horizontal position by ropes and cables running between ship and ground. By the presentinvention, in which one object' is to effect promptstabilization or lev elling of a moored airship,means are provided forautomaticallyvarying a load 011 the free end of theship, increasing it if the free end moves upwardand decreasing it if downward movement takes place. The ship may normally carrylthe said load, ormay 4 pick it up from the ground on arrival.

.. M Essentially, the automatic stabilizing apparatus of the present invention consists of means having variable effective weight, hanging or otherwise supported on the airship. Preferably, said' means is attachedto Seria1 No. 499,727.

the airship at a point remote from the moored end of the ship, being therefore movable with the free end, and preferably also it extends to and is supported by a horizontal plane beneath the ship, as by the ground or by a platform above the ground. It is desirable, although not strictly necessary, that the effective weight of the automatic stabilizing means vary more or less directly as the distance between the ground and the free end of the ship, so that movement tending to be of great magnitude either upward or downward will be minimized by a corresponding corrective change in the effective weight of the stabilizing apparatus.

A simple method of accomplishing the results made possible by this invention is to provide for the automatic transfer of liquid from a ground reservoir to a tank attached to the ship, and vice versa; so that. an increase in the effective weight thus hanging I on or supported by the. ship is effected automatically in response to an increase in the elevation of the moored end of the airship. Similarly, a very heavy chain may be allowed to depend from the ship to the ground, having asubstantial length lying loosely on the ground, so that upward movement of that part of the ship from which it hangs adds some of the chain to its load, and downward movement subtracts some of the chain from the load. In both cases, the effective weight of the stabilizing means varies approximately as the elevation of the free end of the airship. In place of the chain, any other flexible element with large weight per unit of length may be considered equivalent. 7

In the accompanying drawings:

Figure 1 shows in elevation an airship moored to a travelling carriage on a rotatable tower, together with means for stabilizing the airship by the use of liquid, the weight of which is added to or removed from the airship;

Figure 2 is a side elevation, somewhat diagrammatic and on a larger scale;

Figure 3 is a plan of a stabilizer much similar to that shown in Figure 1;

Figure 4 is an elevation in section on a still larger scale of portions of this apparatus;

Figure 5 is an elevation of a fixed mooring mast with means for stabilizing an airfor by attaching a tank 591 to the airship,

at a point toward the free end thereof, by

means of tackle 592-. A flexible pipe 594 adapted for the fiow of liquid therein connects this tank to a second tank 595 located at a lower elevation,preferably on themooring tower.

Automatic control of the flow of liquid between these two tanks is provided either by apparatus 597 located on the airship, which improvement is the subject of a separate application, Serial No. 498,605, or by means of apparatus, thedetails of which are shown in Figures 2, 3 and 4. The lower tank 595, which is of air-tight construction, is connected by air pipe 601 to the valve'625 and by water pipe 608 to a compression tank 621 which'in turn is connected by waterpipe 609 to a cylinder 622. In this cylinder isa pisto n'623, movable by variations in stopping it when the pressure exceeds a head or pressure of the water against a compression spring 624. To the piston rod 627 isattached the sliding part 626 ofthe valve 625. Air pipes 601, 602, 608 connect the-valve with the tank 595, the compressed air tank 604, and the exhaust,-respectively.

606 is an air-compressor, driven by motor 607, for supplying compressed air to the system. Automatic means areprovided for starting the motor when the air pressure falls below a predetermined amount, and for predetermined amount, but as such means are well known in the art, a detailed description of it is not deemed necessary.

The action of this stabilizing apparatus is as follows:

Assume that the airship 1s moored in a position with its longitudinal axis horizon-' tal, that the slide valve is at the midposition as shown, and that each of the tanks is half full of water, the head or hydrostatic pressure of the water in the upper tank against 'thepiston balancing the action of the spring. When, for any reason, the free end of the airship is forced downward, this pressure is lessened and the piston is pushed by the spring to the left, carrying with it the slide valve and thus permitting air to escape from tank 595 and pipe 601 through exhaust pipe 603 to the atmosphere. This escape of air permits water to flow by gravity from the suspended tank 591 to' the tank 595 at lower elevation, and by thus reducing the weight carried by the airship, restores the airship to its normal position. A similar but reverse action takes place when the free end of the ship is raised, for any reason, above its normal position.

In place of having water flow by gravity from the upper tank to the lower a more rapid stabilizing effect may be obtained by carrying an air pipe from the valve to the upper tank and using the pressure of the compressed airto force water from the upper tank to thelower. As such an arrangement of piping may be simply and easily made, details of it are not herein shown. Also various improvements in the stabilization of airships, described in our separate patent application filed heretofore, on September 6, 1921, Serial No. 498,605, as being applicable broadly to airships, are applicable for stabilizing an airship while moored to a tower, and for automatic control of the stabilizing apparatus herein shown. i

For example, any-suitable control comprising liquid container 597 may be arranged lengthwiseon the vessel, so that a rise or fall of the rear end will tip it and make some flow or change in pressure of the liquid in this container, which may set in motion automatic machinery to turn the horizontal rudder of the'ship. In case a wind is blowing, this may'correct the elevation of the rear end.

Or the rudder may be deflected by changes in head ofliquid in tank 591, asfelt in tanks 595, 621 and 622, through suitable electrical connections made by pistons 623, 626 in the motor circuit controlling the rudder (not shown). Or the motor thus set in motion and referred to as operating a rudder, may operate a pump to shift liquid in'the system to or from tank 591.- Means may be provided according to details shown in'oursaid other application whereby the rate at which said liquid is made to flow increases and decreases respectively assaid freeend moves away from and toward its normal elevation with respect to the moored end of the airship.

InFigures 5, 6, and 7, an airship 1 is shown attached to a revolvable' collar 551 at the top of the fixed mast 541 by means of a universal joint, which by having axes of rotation at right angles to each other provides for movement in any direction. The part 555, rotating in the collar 551, provides for rotating movements of the airship about its longitudinal axis, While the collar 551,

revolvable about the centerTpin 556 of the mast, permits swing of the airship around the mast. Members 552, 553 and 557 make possible vertical'mov'ement of the free end of the airship. Suitable guy-lines 542 are used for bracing.

-a long, heavy chain 571is attached to the For maintaining the airship'in a horizontal-position while moored to the mast,

suspended therefrom.= Weight is removed from the airship on the lowering ofits free end, and is added thereto on the raising thereof, thus providing a means of stabilizing the airship in its normal horizontal position In place of the simple chain 571,

heavy weights 581 may be attached to a made to suit the requirements of particular 7 circumstances. i iploy a pendulum control for the stabilizing chain 582 or other flexible cable, as shown in Figure 7. I

'Moditications'in the invention may be Thus'it is possible to' emsystem, operating thereby a switch electrically wired to the motor. Other changes may be made as desired. 1

The subject matter of this application constitutes matter divided out of our application 502,127, filed September 21, 1921, for Improvements in means for mooring and housing airships. It is intended that the patent based on the present application shall cover, by suitable expression in the appended claims, whatever features of patentable novelty reside in the particular inventionhere--- in disclosed.

earths surface and the free end of the air- I We claim as our invention: 1. Apparatus for stabilizing an airship attached near its end to a moor ng device com- 10 prising depending movement-resisting means *the effective weight of which is variable ap proximately as the distance between the ship, said depending movement-resisting means at its upper end, movable with the free end of the airship, being attached to the airship at a point remote from the moored end thereof and at its lower end,

relatively fixed,'being independently supported on a horizontal plane beneath the airship.

2. Stabilizing apparatus for an airship comprising a chain attached to the airship a reservoir beneath theairship, and means for transferringliquid between said reservoirf and said tank.

4. In apparatus for stabilizing an airship while at a mooring station, the combination of a tank; for liquid; means for attaching said tank to an airship and for detaching" same; a second tank for liquid, located at the mooring station; a pipe connecting the two "tanks, through which pipe said liquid may flow back and forth between them; and

means for controlling said flow, actuated by 5. In apparatus for stabilizing an airship while at a mooring station, the combination of two tanks for liquid, one removably attached to said airship toward the free end thereof; a pipe connecting them, through which said liquid may flow back and forth between them; and means for controlling said flow, actuated by variation in pitch of g the longitudinal axis of said airship; where by said airship is automatically maintained in an' approximately horizontal position;

6. In apparatus for mooring an airship, the combination of a tower; a horizontal revolving head on, said tower; means for fastening the bow of an airship to said revolving head; a tank for liquid, removably attached to said airship toward the stern thereof; a second tank, for liquid, located at the tower head and revolving therewith; a pipe connecting said tanks, through which pipe said liquid may flow back and forth between the two tanks; a quantity of said liquid in the system; thereby to maintain said airship approximately in a state of horizontal equilibrium; and automatic means for controlling said flow of the liquid from either tank to the other, actuated by a variation in the pitch of said airship from a hori- 'a fixed vertical axis; means for fastening the bow of an airship to said tower; a tank for liquid, removably attached to said airship toward its stern; a second tank for liquid,

located at the tower and revolving therewith; a pipe connecting said tanks, through which said liquid may flow back and forth between the tanks; a quantity of said liquid in the system; and automatic means for controlling said fiow of the liquid, actuated by a variation in the pitch of said airship from 'a horizontal position, thereby maintaining said airship approximately in a state of horizontal equilibrium.

8. In equipment for stabilizing an airship while moored by one end to a tower, the combination of two tanks for liquid, one .attached to the airship at a point toward its free end and the other located at a fixed elevation;'a pipe through which said liquid may. flow back and forth between the two tanks; a quantity of said liquid in the system, and means, actuated by changes in head of the liquid for controlling said flow of liquid, whereby the free end of the airship is maintained at tion.

9. .In equipment for stabilizing an airship while moored by one end to a tower, the

combination of two tanks for liquid, one

attached to the airship at a point toward its free end and the other located at a fixed elevation; a pipe through which said liquid may flowback and forth between the two tanks; a quantity of said liquid in the system; a cylinder operatively connected to the fixed tank; a piston movable in the cylinder by changes in head of the liquid; an air valve operated by said piston; a supplytank of compressed air; and pipe connections for admitting compressed air to the fixed tank to oppose the hydrostatic head, whereby the free end of the airship is automatically maintained at practically a constant elevatlOIl. i

10. In. equipment for stabilizing an airship while moored by one end to a tower,.the

combination of a vessel for liquid, attached:

to the airship at a point toward its free end; a cylinder located at a point having a fixed elevation; a pipe through which liquid pressure may be transmitted from the vessel to the cylinder; a quantity of said liquid in the system; a piston movable in the cylinder by' changes of pressure of the liquid due to variations in head of the liquid; and means,

controlled by said movement of the piston,

for deflecting the horizontal rudder of the airship; whereby a stabilizing eiiect is obtained for maintaining the airship in a position in which its longitudinal axis makes an approximately constant angle with the horizontal.

11. In equipment for stabilizing an airship while moored, by one end to a tower,

tity of said liquid in the system; and means for controlling the flow of said liquid between the two tanks, comprising a cylinder,

.a pipe-holding the column of liquid from a point on the airship to said cylinder, a

piston movable therein; means acting on the piston in opposition tothe column head; a source of supply of compressed air; andairpipe connections; whereby, by shifting of a liquid the free end of the airship is maintained at a practically constant elevation.

12. In equipment for mooring and stabilizing airships while at a station, the combination of a mooring tower; means for attaching the head end of an airship to said tower; a multiplicity of weights, depending from and supported} by said airship arranged in progression below it; and other supportfor said weights, the whole being arranged in such a manner that on a move-c practically a constant elevament of the tail end of said airship below its normal position while thus moored, the number of weights exerting a downward pull on the airship will be reduced.

13; In equipment for mooring and stabilizing airshipswhile at a station, the com- ,bination of a mooring tower; means for attaching the head end of an airship to said tower; amultiplicity of weights depending from the airship and arranged in combina tion with other support in such a manner that, on a downward movement of the tail end of said airship, the number of weights exerting a downward pull on said airship will be reduced and, on an upward movement of the tail end, the number of weights exerting a downward pull will be increased.

14. In equipment for mooring and stabilizing airships while at a station, the combination of a mooring tower;means for attachingthe head end of an airship to said tower; and a heavychain suspended from said airship insuch a manner that its lower end rests on an independent support whereby on a movement of the tail endof said airship below its normal position while thus moored, the amount of chain exerting a downward pull on said airship will be reduced. i

15. In equipment for mooring and stabi-' taching the head end of an airship to said tower; and a heavy chain suspended from said airship to earth in such a manner that, on a downward movement ofthe tail end of said airship, the earth carries more of the chain whose downward pull on said airship is thereby reduced; and on an upward movementof the tail end, the amount of chain exerting a downward pull will be increased.

r 16. Apparatus for controlling automatically the operation of mechanism to add to and take off of an airship weight while .moored, comprising a duct containing a liquid column whose upper end is attached to the airship and moves therewith, and whose lower end is fixed in elevation, whereby variations in hydrostatic pressure are produced that are proportional to the vertical variations of the free end of the airship from its normal elevation, and pressure-actuated means, adapted to receive said hydrostatic pressure, for controlling the direction and duration of flow throughjthe duct.

17. In combination 'with an airship fmoored atone end, a stabilizing apparatus comprising a variable load connected to said ,airship and adapted to increase progressively when the free end of'said; airship moves upward and todecrease progressively when said free end moves downward; v

18 In combination with an airship moored at one end, stabilizing apparatus comprisinga heavy body supported in part by the airship, and resting in part upon a fixed support below said airship, and movable gradually from and toward said fixed support; the movements of said heavy body from and toward said fixed support corresponding, respectively, to upward and downward motion of the free end of said airship. Signed at San Bernardino, California, this-eleventh day of November, 1930.

WILFRID V. N. POWELSON. WARREN TRAVELL. 

